I woke up this morning to find that the water feeding the toilets in the house was full of dirt/mud/silt. After taking a look at my well pump system I found that the pressure switch keeps turning the pump on and off every second or two. Each time the switch turns the pump off, the water from the pressure tank discharges back down the line towards the well/pump. After enough pressure is lost, the switch activates the pump again. This repeats ad infinitum.
I believe that the water discharging back down into the well is causing dirt to be kicked up in the well, which makes the water in my toilets filled with dirt since the water line to them isn't filtered.
Any way, what is most likely the problem? It seems that there should be a check valve or something to keep the pressure in the pressure tank / line from escaping back towards the well. Maybe that went bad?
Or maybe the pressure switch went bad? When the switch is turned on for the first time (after letting all the pressure out of the line), the water pressure worked its way up to 80 or 90 psi, and stayed there with the pump on for a minute before the switch turned the pump off... it seemed like the switch should have turned the pump off sooner.
Some basic details: My system consists of a ~100 ft deep well with a submersible pump, a pressure switch (that was replaced about 2 years ago), a control/electrical box for the switch, and a 5 or 10 gallon pressure tank that looks fairly new (it's at least 3 years old).
EDIT: video of the behavior (action starts at 4:10): https://www.youtube.com/watch?v=EfE98N5p1gQ&list=UU-PYeNYSUiTfiH1ZfcD9_cw
EDIT 2: video of pressure behavior when 2 outlets are open letting water run (remains at ~56psi with pump on): https://www.youtube.com/watch?v=oDqSMMJUVXY&list=UU-PYeNYSUiTfiH1ZfcD9_cw
And more info: With the pump off, and pressure on line at 0 psi, I measured the tank pressure and it was at around 65psi - so I'm guessing the bubble/bladder isn't bad? But the pressure might need to be lowered in the tank?
Any help/advice/suggestions you can give me is appreciated! Thanks in advance!